1. Field of the Invention
The present invention relates to a depression cap for a bottle such as a wine bottle, the depression cap being capable of maintaining the internal pressure of the bottle under a predetermined value. In particular, the present invention relates to a depression cap that is mounted to a bottle and equipped with an air pump that can be activated when the internal pressure in the bottle is below a predetermined value.
2. Description of the Related Art
It has been found that a little wine may help with the blood circulation of human being and it is common to use the original cap or cork to reseal the wine bottle that still has wine left inside. However, the sealing effect of the cap or cork was found unsatisfactory such that air leaks into the bottle and causes deterioration of the wine. In addition, the cork might be expelled from the bottle when the interior pressure in the bottle exceeds a certain value.
It is a primary object of the present invention to provide a depression cap that may automatically draw air out of a bottle after the depression cap is mounted to the bottle. The internal pressure of the bottle is reduced to a predetermined value.
In accordance with a first aspect of the invention, a depression cap comprises a first end and a second end, the second end having a compartment defined therein for engaging with a nose of a bottle. An air pump is provided for drawing air out of the bottle. A pressure-activated switch is provided for controlling on/off of the air pump. The pressure-activated switch is capable of detecting an internal pressure in the bottle. The air pump is turned on when the internal pressure is higher than a predetermined first pressure value, and the air pump is turned off when the internal pressure is lower than a predetermined second pressure value that is smaller than the predetermined first pressure value.
In accordance with a second aspect of the invention, a depression cap comprises a first end and a second end, the second end having a compartment defined therein for engaging with a nose of a bottle. An air pump is provided for drawing air out of the bottle. A pressure-activated switch is provided for controlling on/off of the air pump. The pressure-activated switch detects a pressure difference resulting from a closing motion of the depression cap onto the nose of the bottle and turns the air pump on to thereby draw air out of the bottle. The air pump is turned off when an internal pressure in the bottle detected by the pressure-activated switch is lower than a predetermined pressure value.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.